DA: DeSalvo DNA 99.9 percent match in Boston Strangler case

Albert DeSalvo confessed to 13 slayings in 1960s

UPDATED 8:10 PM EDT Jul 11, 2013

BOSTON -

More than 50 years after the "Boston Strangler" terrorized the city, investigators have DNA evidence definitively linking Albert DeSalvo to one of the slayings, Suffolk County District Attorney Dan Conley said Thursday.

DeSalvo confessed to being the Boston Strangler in the murders of 11 women from June 1962 until January 1964, but his confession was deemed inadmissible in court and he was never formally charged. He also confessed to the murders of two other women.

Conley said familial DNA evidence was used to link DeSalvo to the Jan. 4, 1964, homicide of Mary Sullivan, 19, in her Charles Street apartment.

Conley said DNA evidence was collected from stains on a blanket on which Sullivan's body was found. In 1964, there was no DNA testing but when it was tested decades later, the stain was found to contain two DNA profiles -- the victim and an unknown male, Conley said.

"Given the facts and circumstances in this case, there can be no doubt that the male DNA belonged to the individual who murdered and raped Mary Sullivan," Conley said.

Using DNA collected from a water bottle discarded by DeSalvo's nephew, investigators were able to make a familial DNA link to DeSalvo.

Conley said the Y-chromosome from the nephew indicated he was related to the male whose Y-chromosome was present in the sample taken from the Sullivan crime scene.

"This is good evidence, strong evidence and reliable evidence. But it is not sufficient to close the case with absolute certainty," Conley said.

Conley stressed the DNA link only ties DeSalvo to Sullivan's death, not the other Boston Strangler slayings. Investigators are still sorting through evidence in the other Strangler cases.

DeSalvo family attorney Elaine Sharp said the DNA link does not prove DeSalvo was Sullivan's killer.

"Just because you find DNA on somebody's body and you say it's connected to the defendant, doesn't mean the defendant murdered the victim. I think that is very important. You have to take everything in context," Sharp said.

DeSalvo, who was married with children in the 1960s, was stabbed to death in prison in 1973 when he was 42. He is buried at Puritan Lawn Memorial Park in Peabody, Mass.

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Boston Strangler Victims

Between June 14, 1962 and January 4, 1964, 13 single women (between the ages of 19 and 85) were murdered in the Boston area.